﻿Electrical Changes induced by Ultraviolet Liglit. 101 



phenomenon also denotes a disruption or disintegration of the 

 atoms of such matter; although up to the present our know- 

 ledge as to the products is purely conjectural. The inference 

 of! transmutation, however, is justifiable: and the following 

 experiments constitute a first attempt to ascertain the extent 

 and the manner in which ordinal')* forms of matter disinte- 

 grate, whether they be elementary or compound. The order 

 of affinity of the atoms of elements for electrons, which they 

 part with during the process of disruption or disintegration, 

 will be seen to be the same, in the main, as that which they 

 manifest towards electrons, the loss of which converts them 

 into ions. 



If it turns out to be true, as Soddy claims to have shown 

 ( ; Nature/ Aug. 2nd, 1906), that a disintegrating element, 

 which parts with /3-rays or electrons, leaves behind it matter 

 not associated with a positive charge; and if it be also true 

 that such "disintegration" implies transmutation into some 

 other form of " elementary " matter, then it may be that the 

 phenomena, of which a description is given in the folio wing- 

 pages, refer to cases of transmutation. When zinc, for ex- 

 ample, illuminated by ultraviolet light, parts with corpuscles, 

 it may be that the residual matter, the zinc minus electrons, 

 is no longer zinc, but some other form or forms of quasi- 

 elementary matter. 



If these views be adopted, it would appear that electrons are 

 capable of associating themselves with matter in three ways : 

 First, as a surface-film. When electrons are removed by 

 friction their absence is termed " positive electrification." 

 Secondly, in a condition analogous to that of one element in 

 a chemical compound: an ion of chlorine, for example, is 

 " chlorine-stuff'' plus an electron; common salt is a compound 

 of "sodium-stuff"'' with ''chlorine-stuff," and an electron. 

 A "positive ion'' would then consist of an elementary "stuff," 

 unassociated with an electron or with any other kind of atom. 

 And lastly, it may be conceived that if an atom of element 

 loses one or more electrons without leaving the remainder 

 positively charged, that " elementary " matter will change 

 its nature : it will cease to be the original element, but will 

 be transmuted into atoms of lower atomic weight; or, it may 

 be, several such " residues " may associate themselves to build 

 up an atom of higher atomic weight. 



These, as already remarked, are observations of a specula- 

 tive character : but in carrying out research U is necessary 

 to form some kind of hypothesis in order to guide experiment 

 Should the hypothesis not be substantiated by observation, a 

 new T one will become necessarv. 



Phil. Mag. S. 6. Vol. 12. No. 70. Oct. 1906. 2 D 



